When the Eagles left the Etihad stadium with three goals and three points from the reigning and future champions of England, they knew they'd caused one of the upsets of the season.
But the manner in which they defeated Manchester City 2-3 stands out, too, with Townsend's goal earning him the club's Goal of the Season and a place in the history of players synonymous for scoring screamers.
The game began as many had predicted, with City taking the lead through Ilkay Gundogan just 27 minutes in. When Jeffrey Schlupp retaliated six minutes later, however, a Palace shock seemed possible. Townsend's thunderstrike flew in two minutes after and suddenly the Etihad sat up to pay attention.
Luka Milivojevic netted a penalty early into the second-half and astonishingly Palace were protecting a two goal lead against the champions of England with just five minutes of time remaining.
Kevin De Bruyne's 85th-minute goal may have teed-up a nailbiting ending, but Palace held on to a cherished three points.
It's certainly one of the Eagles' stand-out upsets, but is it the greatest moment Palace has enjoyed over the last decade? Or does something else edge it out? Vote below!